Tube forming apparatus



Sept. 14, 1937. F, MULLE 2,093,155

TUBE FORMING APPARATUS I Filed. Dec. 5, 1934 3 Sheets-Sheet l Sept. 14, 1937. F. MULLER TUBE FORMING APPARATUS 3 Sheets-Sheet 2 Filed Dec. 5, 1934 IIIIL Mllllllllllllfllllllllllllllllll! Sept. 14,1937. F. MULLER TUBE FORMING APPARATUS Filed Dec. 5, 1934 3 Sheets-Sheet 3 zk a '6 and consequently with the carrier I l.

Patented Sept. 14, 1937 UNITED STATES PATENT OFFICE Trust Company,

Elizabeth, N. J., executor of said FriederichMiiller, deceased Application December 5, 1934, serialNa'vseozs Claims.

This invention relates to a novel and improved tube-forming apparatus of the general type shown in my prior Patents 1,783,384 and 1,819,376. The novel features will be best understood from the following description and the annexed drawings, in which I have shown a selected embodiment of the invention and in which:

Fig. 1 is a plan view of the apparatus selected for the illustrative embodiment;

Fig. 2 is a side elevation of the structure appearing in Fig. 1;

Fig. 3 is a vertical sectional view taken approximately on the line 33 of Fig. 1;

Fig. 4 is a partial section on an enlarged scale taken approximately on the line 4-4 of Fig. 3,

but showing the hammers withdrawn;

Fig. 5 is a fragmentary View taken on the same plane as Fig. 3, and showing the parts at the right-hand end of that figure in positions which they may occupy when performing work upon a tube;

Fig. 6 is a view similar to Fig. 5 but showing the parts in still another relation, and showing a different formation of tube being made by the I swaging head;

Fig. '7 is a view of a section of tube before having the work performed thereon by my novel apparatus;

Fig. 8 shows a longitudinal section of the same tube after having been operated upon by my novel apparatus; 7

Fig. 9 shows a longitudinal section of another form which the tube of Fig. '7 may be made to take and illustrating the variety of forms which may be achieved by my novel apparatus.

The apparatus is shown as mounted on a base I, which may be made of any suitable form and which comprises bearings 2 and 3 rotatably sup porting a hollow spindle 4 which may be rotated by any suitable driving means, here shown as a pulley 5.

Rotatably mounted within the spindle and concentric therewith is a hollow shaft 6. The spindle is enlarged at one end to form a chamber '1 surrounded. by a cylindrical wall 8. The shaft 6 extends within the chamber 1, where it is likewise enlarged to form a head 9 slidably contacting with the wall 8.

The wall 8 and head 9 form part of the swaging head, the rest of which is composed of-a plate iil rigidly secured to the wall 8 and having secured thereto a hammer carrier II disposed coaxially with the hollow shaft 6. The head 9 has a recess [2 therein, likewise coaxial with the hollow shaft Mounted within this recess is a cam l3, which may be secured in place by a collar 14 so as to move with the head 9.

The cam I3 is shown as being wedge-shaped, as

seen in Fig. 3, and as having an undulating suri presently.

The work will normally be in the form of a tube, which has been omitted from .Fig. 3 but which 1 is shown in Figs. 5 and 6. Such a tube will be placed within the bore of the hollow shaft 6 and surrounding the mandrel I6 within that bore. The end of the tube will then be disposed upon the stud H: in the draw-head l8,'where itxmay be secured by means of the chuck shown generally at I9. The details of this chuck may be the same as those shown inmy aforesaid Patent 1,783,384, or ofany other suitable form. 7

Suitable mechanism to be more fully described presently is provided for moving the draw-head away from the swaging head and thus moving the tube along the mandrel and through the swaging head. At the same time,th'e spindle may be rotated with respect to the hollow shaft, thus carrying with it the hammer carrier and the hammers while holding. the cam relatively stationary so that the'action of the cam uponthe hammers is to cause a series of rapidlyrepeated blows of the hammersupon the tube as it is being drawn past the hammers. A relatively slow r0- tation of the cam itself is provided sothat any one hammer will move circumferentially of the I tube between blows, thus avoiding a concentrated hammering upon a narrow area extending lengthwise of the tube.

The rotation of the cam may be accomplished by an electric motor 20 havinga worm 2| engaging a worm gear 22 secured to the hollow shaft which, as noted above, has thecam rigidly secured thereto. The motor and gearing may bev so arranged as to cause the proper speed of rotation of the shaft and cam which, of course, is much slower than the speed of rotation of the spindle carrying the hammers. If desired, the tube may be rotated instead of the cam, for example in :some such manner as described and shownin my aforesaid Patent 1,819,376.

The draw-head, instead of beingoperated 'by a feeding screw as described in my aforesaid lower is shown as being urged into engagement with the cam groove by a spring 27 acting against a handle 28 which may be used to actuate the follower to remove it from the groove. The follower is preferably provided with a roller engaging the groove, as indicated.

The frame 26 is slidably mounted upon tracks 29, and, if desired, may be manually moved along the tracks by a hand-Wheel 30. This hand-wheel may operate a drive similar to that described in my Patent 1,783,384, and which will cause movement of the frame 26 along the tracks 29. In

said patent, such an arrangement is shown in connection with a screw, whereas in the present instance I replace the screw by a rack 3| which may engage a pinion operated by the hand-wheel 38. Since such arrangements are so well known in the art, no further detail description or illustration thereof is deemed necessary.

The tube may be formed into various shapes as .it is drawn through the swaging head. As set forth in my said Patent 1,783,384, by drawing the tube through the swaging head. at a uniform speed, a tube, such'as shown at 32in Fig. 7 and which is of the usual cylindrical form, may be drawn out into a uniformly tapered. tube, such as shown at 33 in Fig.8. In Fig. 9, at 34, I have shown the same tube 32 formed into such a shape as may be adapted for part of a piece of furniture. The various peculiar formations seen in Fig. 9 may be obtained in part by varying the speed at which the tube is drawn and also by causing an additional movement of the mandrel and cam 13 lengthwise of the tube. The resultant of the speed of the draw-head on the one hand and of the mandrel and cam l3 on the other hand will determine the shape which the tube is to take. The mandrel is cylindrical through the major portion of its length, to conform with the shape of the tube which surrounds it, but at its end within the swaging'head'it is provided with a-conicalshaped point 35, the surface of which'preferably has its longitudinal elements exactly parallel to the longitudinal elements of theundulating surface of the cam l3, so that the. thickness of the tube ismaintained uniform.

The head 9 and the mandrel l6 are secured together through a connection 36 at the left-hand end of the shaft 6, for example inv the manner described in my aforesaid Patent 1,783,384, and which is plainly shownin Fig.3 and therefore will not be repeated here in detail; It'is' enough to say that movement of the head 9 and consequently of the cam l3 towards the left will be accompanied by a movement of the mandrel in the same direction and'to the same extent, and the result, as plainly shown in Figs. 5 and 6, willbe that the further these parts are moved towards the left, the further. may the hammers l5 be moved radially inwardly towards the center of the tube. This in turn means that the tube may be reduced to a smaller diameter and, as noted above, the-speed at which this'reduction takes place, and consequently the taper of the tube, is

dependent upon the relative speeds at which the draw-head'on the one hand, and the cam and mandrel on the other hand, are moved. 7

Similarly, movement of the cam and mandrel towards the right will cause the tube to be formed of larger diameter, and here again the'speed at which this takes place, and consequently .the

taper of the tube, will depend upon the relative speed of movement of the draw-head on the one hand and the cam and mandrel on the other hand. In either case it will be seen that the hammers remain in the same position as measured lengthwise of the tube, and the cam and mandrel are moved lengthwise with relation to the hammers while the tube is drawn past the hammers. Of course, it is to be understood that the tube may for short intervals of time be held stationary while the hammers act thereon, this depending upon the shape of the cam groove 24.

To. provide the longitudinal movement of the cam and mandrel, I have provided a novel device which is mounted on a shaft 38 in fixed bearings in the base, so as not to have any lengthwise movement on the base. slidably mounted on tracks 39 and 40 is a slide 4| having a pedestal 42 carrying themotor20 and having a bearing in which the hollow shaft 6 may rotate. At the same time, the pedestal 42 is' held against movement lengthwise of the shaft 6 by any suitable means, such as-that illustrated in Fig; 3, and comprising a ball bearing 43 between the gear 22 and the pedestal. The shaft .6 may also be provided with a block 44 slidably mounted upon a bracket 4570f the base, and the shaft may likewise be slidably received in a bearing 46.

The slide has slidably mounted thereon a plurality of cam followers, each adapted to be received in a' cam groove inthe drum 31. In the present instance, these cam followers, which are designated and 48, are pivotally connected to a rocking arm 49 which is pivoted at 50 upon the pedestal 42 and has a lug 5| engaging a spring 52 received in a recess in the slide.

The arrangement is such that when the lug 5| is on one side of the point 53 of the spring, the arm 49 will be cammed on its pivot so as to bring one of the followers into a cam groove in the drum 37. These cam grooves correspond in number to the number of followers, and the engagement and disengagement of the followers is made automatic.

This automatic engagement and disengage ment may be achieved'by providing at the end of each cam groove an inclined surface, such as respectively, from which it will be seen that as,

for example, the follower 41 reaches the incline 54, the follower will be raised out of the groove and the follower 48 will be lowered into the groove 58. While this action is taking place, a slight pause may be arranged in the cam groove 24 of the drum 23.

Theabove arrangement is one which makes it possible to provide any desired number of backwardand forward movements of the cam l3 and the mandrel, inspite of the fact that the length of the'travel of these parts is limited. For example, the cam groove 5'l'may be shaped so as to provide a uniform taper of the tube upon which work is being done, and the groove 58 maybe so shaped as to cause a gradual increase of size of the tube together with any peculiar or distinctive shapes which may be desired. The two cam drums 23' and 31 are operated independently, this being so that their speeds may be varied as desired and so that'by variation of the speeds and shapes'of cam grooves, any desired configuration of tube can be obtained.

As one revolution of the drum 3'! is completed and thus the possibilities of one cam groove on that drum, such as the groove 5?, are exhausted, the cam follower which has been engaging in that groove will automatically be removed from that groove and a second cam follower will be caused to engage within another groove. In this way, the usefulness of the cam drum 3'! is not limited to one revolution, nor is it limited by the length of travel of the cam l3.

When the machine is started, the follower 47 will be substantially in engagement with the in clined surface 54 so that, as the cam drum 3? is rotated, the follower will engage in the groove 51 until such time as it is forced out of that groove by the inclined surface 5d. The parts are so geared that the cam drum 3? completes one revolution during this time while the follower is in the groove 57. As noted previously, as the follower 41 leaves the groove 5?, that action causes the follower 48 to enter the groove 58 at the inclined surface 58. Then continued rotation of the drum 3! will cause the follower 48 to follow the groove 58 back to the end where the inclined surface is located. This surface will cause the follower to leave the groove, and the follower 4? to be kicked back into the groove 51 at the inclined surface 5 3.

Thus it will be seen that a complete cycle of operations has been completed and the parts are back at their initial positions. At the same time, the movement of the draw-head will be completed. This movement takes place while two revolutions of the drum 3'! take place. In other words, while the travel of the draw-head takes place, the drum 3? makes as many revolutions as there are cam grooves on it. Then the drive operating the draw-head will be automatically or otherwise disconnected in a manner to be described presently, and the follower 25 may be manually removed from the groove 24 and the entire draw-head returned to its initial position, as by the hand wheel and rack 38 and 3|.

The drive may be obtained from a drive shaft 59 which may be operated by a pulley 6G through a clutch 6!. This drive shaft may operate the shaft 62 on which the camdrum 23 is mounted through a train of gearing indicated generally at 63, whereas the shaft 38 of the cam drum 3'! may be operated through a worm gear 64 engaging a worm on a shaft 65, which, in turn, has a worm 66 engaging a worm gear 51 upon the shaft 38. The clutch 5! may be automatically disconnected when a lug 68 on the frame 26 engages a block 69 secured to a rod H! which is operatively connected to a clutch collar 7 I, as plainly shown in Fig. l. The rod 70 may be held in clutch disengaging position by means of a second block 12 engaging a hand-operated latch 13. The block 39 may be adjusted in position on the rod H3 so that the travel of the draw-head may be stopped at any desired point. This should always be after the cam grooves 51 and 58 have completed their work.

In operation, the mandrel may be removed and a pattern may be placed within the bore of the shaft and extending into engagement with the draw-head to which it may be secured. Then the machine may be turned slowly, as by hand, and when the hammers reach a special configuration on the pattern other than the uniform taper, that fact can be readily felt by the operator. In this way, the cam grooves on the two drums 23 and 3'! may be readily marked on blank drums.

When a tube is to be formed, it is secured'to cam grooves, the form of which has been previously determined, will thus reproduce the pattern in the tube.

While I have shown the invention as embodied in a specific form, it is to be understood that various changes in details may be made without departing from the scope of the invention, as defined by the appended claims.

I claim:

1. Tube-forming apparatus comprising a swaging head, a, mandrel centrally disposed in said head, a tubular hammer holder, having a plurality of apertures, surrounding said mandrel but spaced therefrom a sufficient distance to permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of pin-like hammers, each having a work-engaging point, radially movable in the apertures in said holder and adapted to engage a tube and force-it against said mandrel, a cylindrical member having internal tapered cam surfaces adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cylindrical member to force the hammers against the tube, and means to vary the relative positions of said cylindrical member and hammers longitudinally of the tube.

2. Tube-forming apparatus comprising a swaging head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a sufficient distance to permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of pin-like hammers, each having a relatively small work-engaging point, radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cylindrical member having internal tapered cam surfaces adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cylindrical member to force the hammers against the tube, and means to vary the relative positions of said cylindrical member and hammers longitudinally of the tube, said cylindrical member having alternating high and low spots on its inner surface operating a hammer, to cause said hammer to strike repeated blows on the tube wall.

3. Tube-forming apparatus comprising a swaging head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a sufficient distance to permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of pinlike. hammers, each having a work-engaging point, radially movable on said hold-er and adapted to engage a tube and force it against said mandrel, a cylindrical member having internal tapered cam surfaces adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cylindrical member to force the hammers against the tube, means to vary the relative positions of said cylindrical member and hammers longitudinally of the tube, and means to cause a slow relative rotative movement between said tube and cylindrical member.

4. Tube-forming apparatus comprising a swaging head, a mandrel centrally disposed in said head, a hammerholder surrounding said mandrel but spaced therefrom a sufficient distance to the draw-head in the usual way, and then the permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of pin-like hammers, each having a work-engaging point, radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cylindrical member having internal tapered cam surfaces adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cylindrical member to force the hammers against the tube, means to vary the relative positions of said cylindrical member and hammers longitudinally of the tube, and means to cause a slow relative rotative movement between said tube and cylindrical member.

5. Tube-forming apparatus comprising a swaging head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a sufficient distance to permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of pinlike hammers, each having a work-engaging point, radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cylindrical member having internal tapered cam surfaces adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cylindrical member to force the hammers against the tube, said cylindrical member being tapered lengthwise of the tube, and means for moving said cylindrical member lengthwise of the tube in either direction and to a predetermined amount.

6. Tube-forming apparatus comprising a swaging head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a sufficient distance to permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of pinlike hammers, each having a small work-engaging point, radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cam adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cam to force the hammers against the tube, said cam having alternating high and low spots on its surface operating a hammer, to cause said hammer to strike repeated blows on the tube wall and being tapered lengthwise of the tube, and means for moving said cam lengthwise of the tube. in either direction and to a predetermined amount.

7. Tube-forming apparatus comprising a swaging head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a sufficient distance to permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of pin-like hammers, each having a small work-engaging point, radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cam adapted to engage said hammers to force them against the tube, said cam having alternating high and low spots on its surface operating a hammer, to cause said hammer to strike repeated blows on the tube wall and being tapered lengthwise of the tube, means to cause relative rotation between said holder and cam to forcethe hammers against the tube, means for moving said cam lengthwise of the tube in. either direction and to a predetermined amount, and means to cause a slow relative rotative movement between said tube and cam.

8. Tube-forming apparatus comprising a swaging head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a suflicient distance to permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of pin-like hammers, each having a small workengaging point, radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cylindrical member having internal tapered cam surfaces adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cylindrical member to force the hammers against the tube, said' mandrel having a longitudinally tapered surface within said head and said cylindrical member having a longitudinally tapered surface surrounding said tapered surface of the mandrel, and means for moving said cylindrical member and mandrel together lengthwise of the tube in either direction and to a predetermined amount.

9. Tube-forming apparatus comprising a swaging head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a sufiicientdistance to permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of pin-like hammers, each having a relatively small workengaging point, radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cylindrical member having internal tapered cam surfaces adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cylindrical member to force the hammers against the tube, said mandrel having a longitudinally tapered surface within said head and said cylindrical member having a longitudinally tapered surface surrounding said tapered surface of the mandrel and generally parallel thereto, and means for moving said cylindrical member and mandrel together lengthwise of the tube in either direction and to a predetermined amount.

10. Tube-forming apparatus swaging head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a suflicient distance to permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of pin-like hammers, each having a relatively small work-engaging point, radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cam adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cam to force the hammers against the tube, said cam having alternating high and low spots on its inner surface operating a hammer, to cause said hammer to strike repeated blows on the tube wall, said mandrel having a longitudinally tapered surface within said head and said cam having a longitudinally tapered surface surrounding said tapered surface of the mandrel, and means for moving said cam and mandrel together lengthwise of the tube in either direction and to a predetermined amount.

comprising a 11. Tube-forming apparatus comprising a swaging .head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a sufficient distance to permit a tube wall to pass between the mandrelandthe holder, means to draw a tube over said mandrel and through said head, a plurality of pin-like hammers, each having a relatively small work-engaging point radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cam adapted to engage said hammersito force them against the tube, means ,to cause relative rotation between said holder and cam to forcethe hammers against the tube, said cam having alternating high and low spots on its inner surface operating a hammer, to cause said hammer to strike repeated blows on the tube wall, said mandrel having a longitudinally tapered'surface within said head and said cam having alongitudinally tapered surface surrounding said tapered surface of the mandrel and generally parallel thereto, and means for moving said cam and mandrel together lengthwise of the tube in either direction and to a predetermined amount.

12. Tube-forming apparatus comprising a swaging head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a suflicient distance to permit atube wall to pass between the mandrel and the holder, means to draw a tube over said mandreland through said head, aiplurality of pin-like hammers, each havingia relatively small work-engaging point, radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cam adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cam to force the hammers 40 against the tube, means to cause a slow relative rotative movement between said tube and cam, said mandrel having a longitudinally tapered surface within said head and said cam having a longitudinally tapered inner surface surrounding said tapered surface of the mandrel, and means for moving said cam and mandrel together lengthwise of the tube in either direction and to a predetermined amount.

13. Tube-forming apparatus comprising a swaging head, a mandrel centrally disposed in said head, a hammer holder surrounding said mandrel but spaced therefrom a sufficient distance to permit a tube wall to pass between the mandrel and the hold-er, means to draw a tube over said mandrel and through said head, a plurality of pin-like hammers each having a relatively small work engaging point radially movable on said holder and adapted to engage a tube and force it against said mandrel, a cam adapted to engage said hammers to force them against the tube, means to cause relative rotation between said holder and cam to force the hammers against the tube, means to cause a slow relative rotative movement between said tube and cam, said man- 5 drel having a longitudinally tapered surface within said head and said cam having a longitudinally tapered surface surrounding said tapered sur-- face of the mandrel and generally parallel thereto, and means for moving said cam and mandrel 7 together lengthwise of the tube in either direction and to a predetermined amount.

14. Tube-forming apparatus comprising a swaging head, a draw-head disposed in line with said swaging head, means to secure a tube to said 75 draw-head. to be d a n e eby through said swaging head, swaging means. on saidswaging head adapted to act upon said-tube while being drawn through said swaging head, a. rotating drum having a plurality of cam groovestherein, means connected with said swaging heads and adapted successively to engage said cam grooves to move said swaging means longitudinally of said tub-e, a cam controlling said draw-head and causin openings in said tubular holder and radially movable. with respect to said mandrel, each hammer .havingia. Ework-engaging point adapted to operate upon a tube engaging the mandrel and having ahead disposed a'short'distance outside of said holder, a longitudinally. inclined cam disposed outside saidi-holder andclosely adjacent thereto and adapted toengageesaid hammers to force them-against the tubes, 1 said cam having alternate high and low spots on-"its innerrsur face circumferentially thereof, .and means to cause relative rotation 'betweenzsaidholder and cam-to cause vibration of said hammersagainst a tube on; the mandrel. i

16. Tube-forming apparatus comprising] a swaging head, a mandrel; centrally disposed-in said head, a tubular hammer holder surrounding said mandrel but spaced therefrom a suflicient distance to permit a tube wall to pass between the mandrel and the holder, means to draw a tube over said mandrel and through said head, a plurality of short pin-like hammers mounted in openings in said tubular holder and radially movable with respect to said mandrel, each hammer having a work-engaging point adapted to operate upon a tube engaging the mandrel and having a head disposed a short distance outside of said holder, a longitudinally inclined cam disposed outside said holder and closely adjacent thereto and adapted to engage said hammers to force them against the tubes, said cam having alternate high and low spots on its inner surface circumferentially thereof, means to cause relative rotation between said holder and cam to cause vibration of said hammers against a tube on the mandrel, and means to vary the relative positions of the cam and hammers longitudinally of the tube.

1'7. In a tube swaging machine, the combination of a swaging head, a work-drawing head cooperating therewith, and swaging means carried by said swaging head, a portion of said swaging head being shiftable longitudinally to cause said swaging means to vary the diameter of the tube therein; with means for shifting said portion of the swaging head comprising a slide, means connecting said slide with said shiftable portion, a rotating cam drum having in its periphery a plurality of cam grooves, a plurality of cam followers carried by said slide, each adapted to cooperate with one of said cam grooves to shift said slide and swaging head longitudinally, and automatic means for successively shifting said followers into and out of said cam grooves to give to the shiftable portion of the swaging head a predetermined cycle of axial movement while the Work is drawn therethrough.

18. Tube-forming apparatus combining a swaging head, a draw-head disposed in line with said swaging head, means to secure a tube to said draw-head to be drawn thereby through said swaging head, swaging means on said swaging head adapted to act upon said tube while it is being drawn through said swaging head, a plurality of unlike cams and a corresponding number of cooperating elements connected with said swaging head to shift a portion of said swaging head back and forth longitudinally of said tube, means actuated by the shifting movements of said portion to vary the diameter of said tube, automatic means for successively rendering effective said cams and their cooperating elements, means to move said draw-head lengthwise of said tube, and means for simultaneously actuating said draw-head moving means and said swaging head shifting cams. i

19. Tube-forming apparatus combining a swaging head, a draw-head disposed in line with said swaging head, means to secure a tube in said draw-head to be drawn thereby through said swaging head,'swaging'means on said swaging head adapted to act upon said tube while being drawn through said swaging head, a rotatable cam drum having, in its outer periphery, a plural ity of cam grooves, one of which has a radially inclined surface at one end, a slide operatively connected with said swaging head to move a portion thereof axially of said tube, means actuated by the axial movement of said portion to cause said swaging means to vary the diameter of said tube, a plurality of cam followers carried by said slide and each adapted to engage one of said cam grooves thereby to cause said slide and the said portion of said swaging head to be shifted thereby, and means for shifting one of said followers into its complemental cam groove as another follower is shifted out of its groove by the radially inclined end thereof.

20.. Tube-forming apparatus combining a swaging head, a draw-head disposed in line with said swaging head, means to secure a tube to said draw-head to be drawn thereby through said swaging head, swaging means on said swaging head adapted to act upon said tube while it is being drawn through said swaging head, a portion of said swaging head being shiftable longitudinally to cause said swaging means to vary the diameter of the tube therein, means for giving to said draw-head a single uni-directional movement for one complete operation of the apparatus, and means for giving to the shiftable portion of said swaging head a plurality of oppositely directed longitudinal movementsfor each uni-directional movement of said draw-head, comprising a rotatable but non-translatable cam drum, meansvfor giving said drum one rotation for each operative movement of said draw-head, a plurality of cam grooves formed in said cam drum,'a cam follower for each of said grooves, means connecting said cam followers with the shiftable portion of said swaging head, and automatic means for shifting-said cam followers successively into and out of said cam grooves during'a uni-directional movement of said draw-head.

V FRIEDERICH MiiLLER. I 

